Grade indicator for trenching machines



N 6, 19 3- w. G.VAI 1 VOORHIS GRADE INDICATOR FOR TRENCH'ENG'MACHINES Filed ,Sept. 25, 1942 2 Sheets-Sheet 1 Nov. 16, 1943. w. a. VAN VOORHIS GRADE IND ICATOR FOR TRENOHING MACHINES Filed Sept. 25, 1942 2 Sheets-Sheet 2 Patented Nov. 16, 1943 GRADE INDICATOR FOR TRENCHING MACHINES William G. Van Voorhis, Findlay, Ohio, assignor to The Buckeye Traction Ditcher Company, Findlay, Ohio, a corporation of Ohio Application September 25, 1942, Serial No. 459,632

. 9 Claims.

This invention relates to excavating machines but more particularly to wheel type excavating machines which are equipped with an excavating wheel having a series of excavating buckets disposed at the rear of the machine. The invention is primarily concerned with grade indicators for machines of this character for enabling the operator to maintain the desired grade in the excavated trench or ditch, this being particularly necessary in the excavating of tile receiving trenches.

Heretofore excavating machines of the above character have been equipped with grade indicators in the form of sight rods carried by the digging wheel frame at the rear of the machine. In one case the operator was located at the rear end of the machine in order to observe the sight rod but this has proved objectionable because of the complicated controls which are necessary. One set of controls was arranged in the normal position intermediate the front and rear ends of the main frame and a duplicate set of controls was arranged at the rear of the machine in the position occupied by the operator during the digging operation. Obviously this not only added substantial expense to the machine but also reduced the efficiency of the operation and was somewhat unsightly.

Another method used heretofore was to arrange the grade stakes at the rear of the machine, the operator occupying the normaldriving position intermediate the front and rear ends of the machine. However, in this case the operator must notonly watch rearwardly to keep the sight rod aligned with the grade stakes but must also keep watch ahead to prevent the machine from advancing transversely out of the intended line of travel. Manifestly considerable difficulty was involved in keeping watch contin uously in both directions.

Objects of this invention are to overcome objections inherent in the prior methods above mentioned; to produce a sight rod arrangement for wheel type excavating machines which is convenient to the operator in the normal operating position of the machine sufiiciently forward thereof to afford greater vision ahead while also enabling him to observe and control the digging operation readily and conveniently, thereby requiring but a single set of controls; to produce a sight rod for such machines which is automatically responsive to vertical movement of the front end of the machine for compensating for such movement without substantial alteration to the initial settingof the sight rod; to enable bump in the surface of the ground convenient manual adjustment of the sight rod to enable it properly to be aligned with a particular grade stake; and to produce a sight rod structure arrangement having the new and improved features of construction and arrangement indicating mechanism showing the grade indicator and cable connections between it and the digging wheel frame; and

Figure 3 is a view similar to Figure l indicating by broken lines the position of the parts when the front wheels of the machine encounter a depression in the ground surface.

The illustrated embodiment of the invention comprises a wheel type excavator having a main frame I9, thefront end of which is supported by a pair of rubber tired wheels II, the rear end of which is supported by sets of tandem rubber tired wheels i2. Fixed to the rear end of the main frame H3 is a pair of laterally spaced upright beams or elevator rails I3 on the upper ends of which is a sheave arrangement l4 over which cables pass to a digging frame l5. The forward end of the cables are suitably connected to winches I6 as will be readily understood by those skilled in this art. Suitably carried by the digging frame I5 is a digging wheel I! equipped with a series of spaced excavating buckets I8. Digging wheels of this character are well-known in the art so that more detail description is not considered necessary. It is to be understood that during the digging or excavating operation, the digging wheel frame is is supported in the trench in a well-known manner by a shoe or runner, which rides along the bottom of the trench, such as shown in the patent to Krupp 1,081,454, dated December 16, 1913, and also by the front cables, the cables leading to the rear portion of Disposed in the rearward portion of the frame I is the operators seat 29 directly in rear of the steering wheel 2| in front of which is arranged the usual instrument panel 22. The operators seat 221 is conveniently disposed to the various controls such as the control levers for operating the digging wheel H, for the winch l 6,for raising or lowering the digging wheel, and for propelling the vehicle.

It will be observed that a portion of the digging wheel frame extends forwardly to the upright beams or elevators l3 where it connects to slides 23 which-ride vertically upon the rear portion of th beams. Only a single elevator rail 13 and slide123 is shown since such disclosure is suflicient for a full 'understandingof this invention. Thus as will be readily apparent to those skilled in this art, thedigging wheel Il may be raised to travelling position when-the machine is taken to or from the'place of operation or can be lowered to any desired extent within certain limitations into the ground during the trench or ditch excavating operations.

The grade indicator :24 is mounted in front of the operators seat as in position conveniently to be observed by the operator. catoror sight rod 24 is inthe form of an inverted .-L so that the upper or horizontal portion of the sight rod can be viewed by the operator and must be in alignment with the cross arms of the grade stakes as will readily-be understood. These stakes are preliminarily arranged in the ground and indicate to the operator thegrade to be es tablished for the ditchor trench. The vertically disposed portion of the sight rod '24 is adjustably connected'by a suitable clamp 25 toa strand 26 of cable, the upper portion of which passes about a sheave 21 mounted on the instrument panel carrying support, and the lower portion of which passes about -a sheav.e-28 suitably -mounted on the frame; Extending downwardly from the sheave '21 is acable strand 29 which passes about a sheave {it also carried by the frame; thence extends rearwardly providing a strand -3| to a sheave 32 mounted on the lower portion of the upright beam or elevator rail I 3. From the sheave 32 the cable extends upwards- 0 a sheave 33; which is carried by an upwardly extending bracket arm .Mwvhich is .fixdto and movable withthe slide 23. Fromthfsheave -33 the cable extends rearwa rdl'y in a substantially horizontal 42 extends downwardly providing the strand 43 to a sheave 44 which is also carried by the elevator rail [3 and at a position slightly above the sheave 32. From the sheave M the cable leads forwardly to the sheave 2B but interposed in this strand is a helical coil spring 45 which is for the purpose of keeping the cable taut.

In use, theoperator first lowers the excavating wheel to the proper depth and adjusts the sight rod 26 so that the upper or horizontal portion thereof is aligned with the cross arm on the first grade stake as will be readily understood. Then as digging progresses, the operator by means of As shown the .indidirection providing the strand '39" which passes aboutfa sneak/e135 carriei'by a bracket .36 .fixed to the'forwardportiono'i the digging wheel frame 15. From the sheave' the cable extends forwardly providing a strand?! to a sheave 33 alsomountedon the upper end of the slide-supported arm 34. v

'The'cable'pas'ses around the sheave 38 and exten'dsrearwardly thereof forming the strand 39 the en'dfporti'on "ofwhich is anchored at t0 the" bracket 156i The opposite end of the cable is aneho'red at M to the upper end of the bracket upperen'd thereof. The "cable from the sheave control lever which is convenient to the oper- -ators seat, gradually lowers or raises the digging wheel so as to excavate a deeper or shallower ditch or trench as governed by the grade stakes. It will be apparent from an inspection of the drawings that the operator is in a position conveniently not only to view the sight rod but also accessible to the control levers so that the adjustment of the digging Wheel can be readily and conveniently effected. As the digging wheel is moved vertically either upwardly or downwardly, this change is correspondingly reflected in the movement either upwardly or downwardly of the sight rod 24. v

It will be manifest that asthe digging wheel moves downwardly the slide 23 and digging wheel frame i5 also move downwardly andsuch movement causes movement to the cable impartinga downward movement to the sight rod. More specifically downward movement of the slide 23 and'the digging frame 15 cause the sheaves 33 and .38 'on'the' bracket arm 34 toz'nove downwardly. Lil'rewise the sheave. 35cm the bracket arm "36 moves downwardly. This movement decreases the: length 'of the strand between the sheave .32, and the bracket armcarrying sheave t3fand fthrough the cable arrangement above described, the sight rod 24 is moved accordir-igly, thedead end 4! of the cable imparting. .a pull on thef' cabl'e' strands passing about the sheaves Z2, M"and""28 causing the sight rod 2 to be r lmoveddownwardly a distance correspondingto the 'downwaramoveinent of the sheave 33 with respect to the 'sh'av'e".32. Likewise any upward'movement of the slide"23 which causes the lengthening of the cablefstrand between the sheaves 33 and '32 causes corresponding upward movement'of the sight'r'od 24 as will be readily understood. 'In brief, it will be understood that thesig'ht rod 24 moves'upwardly or downwardly and'in the same direction and to the same extent as the slide23 so that at all times the operator is able to look at the sight rod to. determineftheoperating position of the digging wheel.

Unless somev means is provided to compensate for'rnovement of the front end portion :of'the machine when a bump or depression of the ground surface is encountered-it will be 'ma'nif'est that the sight rod 24 'willbe inaccurate. This is depicted in the case of a bumpor raisedpo'rtion of the surface on Figure 1 in which condition the machine frame assumes an angular position with the front end elevated somewhat sojthat with the sight rod 24 remaining in the previous positionflthe operator would look. along the "line E whereas the correct line of sight is indicated by the line C. Similarly as depicted in Figure 3, when the front wheels of the machineencounter a depression, the operator would be viewing the sight 'rjod along the lineE assuming that the sight rod remained in its previous position whereas in such a condition the correct line of sight hould be along the line C. 'Such'change in angular position of the machine is compensated for in the above described cablearrangement.

Specifically the strands34, 31 and 39 act as a compensatory As above explained, one end of the cable is anchored at 40 to the bracket arm 36 and from the anchorage 40, the cable passes back and forth about the sheaves 38, 35 and 33 so that upon upward movement of the front wheels ll of the machine, the elevator rails or upright beams l3- incline rearwardly, for example, to the broken line position I 3a. Since the diggingframe l 5 remainsin a substantially horizontal position during excavation, such angular movement of the elevator rails causes the sheaves 3B and 33 to move closer to the sheave 35 and shorten the length of the strands between these sheaves. Since the cable is kept taut by the coil spring 45, the slack in the compensator strands is taken up by the strands passing about the sheaves 32, 30 and 21 causing the strand'ZS to move downwardly and thereby moving the sight rod 24 downwardly. Similarly it will be manifest from. an inspection of Figure 3 that when the front wheels I! enter a depression or hollow'in the road surface, the elevator rails l3 incline forwardly, for example. to the position indicated by the broken line I311 thereby lengthening the compensator strands and causing the sight rod 24 to moveupwardly. Such compensating movement of the sight rod 24 is controlled in such way that upward and downward move ments of the front wheels do not affect the position of the sight rod relative to the ground surface to any appreciable extent.

From the above description, it will'be understood that the grade indicator or sight rod is conveniently positioned to the operator so that the necessity of having duplicate sets of controls at the rear of the machine is obviated. The operator is located in the most desirable position for efficient operation of the machine both from the standpoint of observing the digging operation. controlling the advancing movement of the machine and controlling the depth of the cut made by the excavating wheel. In the operation of the machine over uneven terrain, the sight rod at all times indicates the position of the digging wheel in spite of upward or downward movement of the front end of the machine. This latter feature is of particular importance in accurately digging a trench of the desired grade. It is manifest that the above described device can be used to advantage on machines other than rubber tired machines, as for example, machines equipped with half length crawlers and any type of round front wheels.

It is to be understood that numerous changes in details of construction, arrangement and operation may be effected without departing from the spirit of the invention especially as defined in the appended claims.

What I claim is:

1. In a ditching machine having a main frame and a digging wheel at one end thereof provided with a series of excavating buckets and a digging wheel frame mounted for vertical adjustments on the main frame, thereby to excavate at different depths, a vertically movable grade indicator on the main frame, and means including a cable and sheave arrangement providing an operative connection between the grade indicator and the digging Wheel frame for causing the indicator to move upwardly or downwardly in the same direction and. to the same extent as the digging wheel frame.

.12..In a wheel mounted ditching machine as claimed in claim-1 characterized in that the grade indicator comprises a sight rod, and means for adjustably fasteningthe sight rodto a cable strand;

3. In a wheel mounted ditching machine having a main frame and a digging wheel at one end thereof provided'with a series of excavating buckets and a digging wheel frame mounted for vertical adjustments on the main frame, thereby toexcavate at different depths, a vertically movable grade indicator on the main frame, and-means providing an operative connection between the grade indicator and the digging wheelframe for imparting movements to said indicator corresponding to vertical movements of 'the digging wheel frame, said means including a device for causing movement of the grade indicator to compensate for angular movement of the front end of the machine due to the frontxwheels encountering raised or depressed ground conditions. J

4. In a ditching machine having a main frame and a digging wheel at one end thereof provided with a series of I excavating buckets and a digging Wheel frame mounted for vertical adjustments on the main frame, thereby to excavate at different depths, a sight rod. on the main frame operatively connected to derive movement from vertical movement of the digging wheel frame, and means for correcting the sight rod inaccuracies due to vertical movements of the front end portion of the main frame.

5. In a ditching machine having a main frame and a digging wheel at one end thereof provided with a series of excavating buckets and a digging wheel frame mounted for vertical adjustments on the main frame, thereby to excavate at diiferent depths, a vertically movable grade indicator on the main frame, and means including a cable and sheave arrangement providing an operative connection between the grade indicator and the digging wheel frame for causing the indicator to move upwardly or downwardly in the same direction and to the same extent as the digging wheel frame, said indicator being positioned a substantial distance forwardly of the rear end of the main frame and in advance of the operators seat.

6. In a self propelled ditching machine having a main frame, an operators seat disposed forwardly of the rear end of the main frame, a digging wheel at one end of the main frame and a digging wheel frame mounted for vertical movements on said main frame, a sight rod mounted for vertical movements in front of the operator's seat to be conveniently observed therefrom, and mechanical means responsive to digging wheel frame movements for causing corresponding movement to the sight rod, thereby to enable the operator by observing the sight rod and comparing same with the usual grade stakes to determine proper positioning of the digging wheel.

7. In a self propelled ditching machine, a main frame, front and rear wheels on said main frame, upright elevator rails at the rear end of the main frame, a digging wheel frame mounted for vertical movement on said elevator rails, a

digging wheel carried. by said digging wheel frame,

an upright bracket arm carried by the digging wheel frame in the region of said elevator rails,

a grade indicator mounted for vertical movements forwardly on said main frame an end= less cable on which said grade indicator is mount 'ed,=she'a'ves over which said cable passes including a sheave on-said' bracket "arm, sheaves on said elevator rails; and sheaves on said'main frame whereby the vertical movements of said bracket arm imparts movement to said endless cablem'adsing "corresponding 'up or down 'fno'vement of -the sightr0d.-

'BuIn a self propelled ditching machine, a main frame; from and rear wheels on said main frame, upright elevator rails at the rear end of the main frame, a digging wheel frame mounted for.--verti'cal movement on said elevator rails,"a diggingwheel carried by sai'd'digging wheel frame, an"-up'rightbracket arm carried by the"digging wheel framein 'th'e reg'ion of 'said elevator rails, a grade indicator mounted for vertical movements'forwardly on said main franiegan endless cable .onnwhi'ch said grade indicator is mounted, sheaves "over which said cable is trained including sheaves 'on said bracket arm and sheaves on 'saiddigging Wheel frame 'spac'edirearwardly from said bracket arm carried sheavesfa'nanchor for on'e'end of the cable on-said bracket arm and an anchor on the digging whee-1' frame for the other'end of said cable, the cable-strands passing' from the sheaves 'on the bracket arm to the sheaves on'said. digging wheel frame compensating for angular movements of said main frame, vertically spaced sheaves on said elevator rails and sheaves onthe main frame, the arrangement being such that up and down movement of the bracket arm transmits like'movement to the grade indicator, and resilient-means for maintaining the'cable taut;

9. In a ditching machine having a main frame and a digging wheel at one end thereof provided with a series of excavating buckets and a digging wheel-frame mounted-for vertical adjustments on the main frame; thereby to excavate at different depths, a vertically movable grade indicator on the main frame, and means including a; cable and sheave arrangement providing an operative connection between-the grade indicator and the digging wheel frame'for causing the indicator to move upwardly or downwardly in thesame direction and to the same 'extent'as the digging wheel frame, said cable and sheave arrangement also including a compensating'device for correcting inaccuracies in the position of the gradeindicator due to up or down movement of the front end of the main frame caused by encountering depressions or raised'portions of the ground surface. 1 G. VAN VOORHIS. 

